Incandescent lamp



June 14, 1927.

INCANDES CENT LAMP Filed Jan. 24, 1925 Coumms CARBON Mo/vaxmE G. R. FONDA lhventor-z Gov-ton R. Fonda,

His Attorney.

Patented June 14, 1927.

. UNITED STATES eon'ronn. romia,

PATENTOFFIC EQ or scmmnc'ra'n new You, AssmNon-To (mum momma.

.courin'z, a coaronamxon on NEW roux.

8 I mcmnscmrm ap lication ma .ianuar 24; 1925. SeriaJ'No. 4,608.

The present invention comprises an im-" provement in electric incandescent lamps. of the gas-filled type, and it is the" object of ciency as lampsnot so provided, the lam s may be o erated at a higher lighting e ciency wit out decrease of life. l'Vhen lamps I '20 ly consisting of tungsten, the filamentbeing g thus toreduce heat losses. The filamentis I have discovered that ataggiven.lighting increase of-life varies considerably with'difthusch arged with argon containing a small; amount of carbon monoxide are, operated a life of about 1,000 hours, an increase of about two to four per cent in lightingefiiciency is obtained In isolated cases the improvement will be even greater.

my invention toincrease the resistance to l disintegration under operating conditions,

and the mechanical strength of lighting filaments in lamps of this type. 4

' In accordance with my invention marked improvement is efiectedin gas-filled lamps 10 by the addition ofcarbon'monoxide to the ,The burn-out on filament in a gas-filled filling of inert gas in the .lamp bulb. lamp is usually due to a local failure which I ,The accompanying drawing shows for,. occurs before the filament has wasted away illustrative purposes an incandescent lamp by vaporization as much as in a vacuum embodying my invention. lamp.- The beneficial efiect of; the carbon 15 Gas-filled incandescent. lamps are demonoxide appears to -.be lar- 13 due to a scribed in Langmuir'Patent, No, 1,180,159 postponement oi the. time. 0 local failure of April 18,- 1916 and comprise in general, of the filament. a p v I as indicated in the drawing, a sealed-bulb 1, What I 'claim'asnewand desire to secure.

in which is provided a filament 2, ordinari by Letters Patent of the United,'States,is:f-'

1. An incandescent lamp of the gas-filled. type, the gas-filling of which com rises 'a few hundredths of one-per cent 0 carbon monoxide.

2.. An incandescent lamp comprising a sealed bulb, a lighting ffilament therein, agas-filling consisting largely ,of argon and in lesser proportion of carbon monoxide.

3. An incandescent lamp containing a gas at a. ressur'e of the order of magnitude of two-t iirds of. an atmosphere and comprising as a constituent agfew hundredths'of one per supported on holders 3 which .in'turn. are mounted on a glass pedestal 4. The filament: 2 usually is constitutediofv a closelywound' helix to increase its effective diameter and? connected as usual to a screw base 5.. I

During the manufacture the bulb first is carefully evacuated of air andwater vaor and then is charged with a suitable gas. or example, aflfilling of argon at a pressure of about two-thirds of an atmosphere may 3 be provided. The argon gas to advantage cent'of;carbon.monoxide., may contain some nitrogen gas, say ten to 4I A incandescent lamp" ,comprising' a twenty per cent. sealed bulb, ait'ung'sten filamentthereimand a gas-filling comprising a mixture of argon, efliciency the life of a'lam'p 0 this type can nitrogen and .carbon monoxide, the argon v be materially increased, by the addition ofi'largelypredominating msaid mixture and carbon monoxide gasin amounts as little..- liaviiig'- a contentfof carbon monoxide, maas a few hundredths ofone percent. The :t'erially'less than one per cent. 5; An incandescent lamp comprising a ferent lamps which .appears'to indicate that. sealed-bulb, a filament of tungsten therein, a the carbon monoxide re oves, impurities filling of gas inert with respect to tungsten from the filament which are" present in 1Vaat'a' pressure of about'600mm. of mercury. riable amounts in different filaments Iv containing several hundredths on 45 havelobtained, for example, 1) an'addition cent of carbon-monoxide, saidalam being of about to 300 microns o carbon mon substantially devoid of] oxygenv an water oxide (0.15 to 0.30 mm. of mercury) to 600 ,vaporand' being capableof operating-withstmm; of ar on "gas in difierent lamps,' in' longer-life than .a similar-lamp creases'of 11 e ranging from-ten to 0 per wit "carbon monoxide. a 60 cent when operating with the same ligtmg {In witness whereof, I have hereunto set elficiency, Instead of ofera'tiiig lamps conmy hand this 23rd da of 'Januar 1925. f taining carbon monoxi e at e same efiie GOR ON R.-FO A.

iunprovided 

